|The asymmetrical bell-curve is caused by having a North-South|
roof ridge, and by having Sharp Hill to the SouthEast.
|The white line under the Sunbox is sunlight|
reflecting off the underside of the box
Solar Angle and Sun Seeker
The roof ridge is North-South with a 10º azimuth-swivel to south, so our solar midday (sun running axially down the ridge) is 1240. The photo of the Sunbox is taken at 1240 when there is zero shadow either side. The solar altitude at midday solstice is 13.65º, and ten days after the solstice, it's clear from the bright white line of reflected light under the Sunbox that the solar angle at the highest point is still below the leading front edge, i.e. less than 20º (it is 14.65º). It will be 2nd Feb when the highest solar angle is 20º, and after that there will by more of the day when the inclined front face of the Sunbox is incident to the solar angle.
Info on angles comes from the iPhone App called Sun Seeker, nothing to do with posh motor yachts. As you turn it, the iPhone always knows which way to point to the Sun, even during the night. I discovered, while researching for this posting, that the App has detailed functions that I hadn't been aware of before.
Left: Solar altitude each day
Centre: The house was photographed in Summer 2007
Right: The sun path is shown in a circular chart